SOLUTION: find a quadratic equation with roots (4+i)and (4-i)

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Question 49269: find a quadratic equation with roots (4+i)and (4-i)
Answer by longjonsilver(2297) About Me  (Show Source):
You can put this solution on YOUR website!
if the roots are (4+i)and (4-i), then we can say that:

x=(4+i) or x=(4-i)
hence
x-(4+i) = 0 or x-(4-i)=0

Working backwards we then say
[x-(4+i)][x-(4-i)] = 0
(x-4-i)(x-4+i) = 0
+x%5E2-4x%2Bix-4x%2B16-4i-ix%2B4i-i%5E2+=+0+
+x%5E2-8x%2Bix%2B16-4i-ix%2B4i-i%5E2+=+0+
+x%5E2-8x%2B16-4i%2B4i-i%5E2+=+0+
+x%5E2-8x%2B16-i%5E2+=+0+
+x%5E2-8x%2B16-%28-1%29+=+0+
+x%5E2-8x%2B16%2B1+=+0+
+x%5E2-8x%2B17+=+0+

there you go.

jon.